The ubiquitous acetyl-CoA carboxylase is a pivotal enzyme in the synthesis of fatty acids in both eukaryotes and prokaryotes. The importance of this enzyme is needed in the initiating reaction for synthesizing fatty acids, which are very important when used as fuel molecules and providing the building blocks of biological membranes. Acetyl-CoA carboxylase catalyzes the committed step in making ...

The activity of the biotin-dependent enzyme pyruvate carboxylase from many organisms is highly regulated by the allosteric activator acetyl-CoA. A number of X-ray crystallographic structures of the native pyruvate carboxylase tetramer are now available for the enzyme from Rhizobium etli and Staphylococcus aureus. Although all of these structures show that intersubunit catalysis occurs, in the c...

A normal mash diet or a single glucose injection stimulates fatty acid synthesis and increases the total activities of acetyl coenzyme A carboxylase, fatty acid synthetase, and malic enzyme in the livers of neonatal chicks. Feeding and glucose injection caused a decrease in the concentration of free fatty acids and fatty acyl-CoA and an increase in CYglycerophosphate and free CoA. These concent...

A whole-genome scan was conducted on 328 F(2) progeny in a Wagyu x Limousin cross to identify quantitative trait loci (QTL) affecting palatability and fatty acid composition of beef at an age-constant endpoint. We have identified seven QTL on five chromosomes involved in lipid metabolism and tenderness. None of the genes encoding major enzymes involved in fatty acid metabolism, such as fatty ac...

The role of intestinal fatty acid binding protein (I-FABP) in lipid metabolism remains elusive. To address this issue, normal human intestinal epithelial cells (HIEC-6) were transfected with cDNA to overexpress I-FABP and compared with cells treated with empty pQCXIP vector. I-FABP overexpression stimulated mitochondrial [U-14C]oleate oxidation to CO2 and acid-soluble metabolites via mechanisms...

AMP-activated protein kinase (AMPK) consists of three subunits: alpha, beta, and gamma. Two isoforms exist for the alpha-subunit (alpha(1) and alpha(2)), two for the beta-subunit (beta(1) and beta(2)), and three for the gamma-subunit (gamma(1), gamma(2), and gamma(3)). Although the specific roles of the beta- and gamma-subunits are not well understood, the alpha-subunit isoforms contain the cat...

Fructose and lactate markedly stimulated fatty acid synthesis from [lJ4C]acetate in isolated cells prepared from the livers of unfed neonatal chicks (21 or 22 days of incubation). In liver cells obtained from unhatched chicks (19 days of incubation) fructose and lactate had very small stimulatory effects on fatty acid synthesis. The increase in fructoseand lactate-stimulated fatty acid synthesi...

Fructose and lactate markedly stimulated fatty acid synthesis from [lJ4C]acetate in isolated cells prepared from the livers of unfed neonatal chicks (21 or 22 days of incubation). In liver cells obtained from unhatched chicks (19 days of incubation) fructose and lactate had very small stimulatory effects on fatty acid synthesis. The increase in fructoseand lactate-stimulated fatty acid synthesi...

Methylmalonyl-CoA epimerase (MCE) converts d-methylmalonyl-CoA epimer to l-methylmalonyl-CoA epimer in the propionyl-CoA to succinyl-CoA pathway. Only seven cases of MCE deficiency have been described. In two cases, MCE deficiency was combined with sepiapterin reductase deficiency. The reported clinical pictures of isolated MCE are variable, with two asymptomatic patients and two other patients...